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Jingxuan Shan,
Wijden Mahfoudh,
Shoba P Dsouza,
Elham Hassen,
Noureddine Bouaouina,
Sonia Abdelhak,
Ahlem Benhadjayed,
Hager Memmi,
Rebecca Ann Mathew,
Idil I Aigha, Sallouha Gabbouj,
Yassmine Remadi,
Lotfi Chouchane
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ABSTRACT: Genome-wide Association Studies (GWAS) revealed novel genetic markers for breast cancer susceptibility. But little is known about the risk factors and molecular events associated with breast cancer in Arab Population. Therefore, we designed a broad study to investigate the susceptibility and prognostic implications of the GWAS breast cancer loci in the Tunisian population. In a cohort of 640 unrelated patients with breast cancer and 371 healthy control subjects, we characterized the variation of 9 single nucleotide polymorphisms (SNPs), namely rs1219648, rs2981582; rs8051542, rs12443621, and rs3803662; rs889312; rs3817198; rs13387042 and rs13281615. Only 5 out of 9 GWAS breast cancer loci were found to be significantly associated with breast cancer in Tunisians: The rs1219648 (G vs. A allele: OR = 1.36, P = 1 × 10(-3)) and rs2981582 (A vs. G allele: OR = 1.55, P = 3 × 10(-6)) of FGFR2 gene; the rs8051542 of the TNRC9 gene (T vs. C allele: OR = 1.40, P = 4 × 10(-4)); the rs889312 of the MAP3K1 gene (C vs. A allele: OR = 1.33, P = 3 × 10(-3)) and the rs13281615 located on 8q24 (G vs. A allele: OR = 1.21, P = 0.03). Homozygous variant genotypes of rs2981582 were strongly related to lymph node negative breast cancer (OR = 3.33, P = 6 × 10(-7)) and the minor allele of rs2981582 was associated with increased risk of ER+ tumors (OR = 1.57, P = 0.02; OR = 2.15, P = 0.001, for heterozygous and homozygous variant genotypes, respectively) and increased risk of distant metastasis development (OR = 2.30, P = 4 × 10(-3); OR = 3.57, P = 6 × 10(-5), for heterozygous and homozygous variant genotypes, respectively) in a dose dependent manner. The association for rs8051542 was stronger for high-grade SBR tumors (OR = 2.54, P = 2 × 10(-4)). GG genotype of rs13387042 on 2q35 showed a significant association with the risk of developing distant metastasis (OR = 1.94, P = 0.02). The G allele of rs1219648 in FGFR2 and the A allele of rs13387042 on 2q35 indicated a better prognosis by showing a significantly higher overall survival rates (P = 0.013 and P = 0.005, respectively). In conclusion, GWAS breast cancer FGFR2, TNRC9, MAP3K1, and 8q24 loci are associated with an increased risk of breast cancer and genetic variation in FGFR2 gene may predict the aggressiveness of breast cancer in Tunisians.
Breast Cancer Research and Treatment 08/2012; 135(3):715-24. · 4.43 Impact Factor
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ABSTRACT: Chronic hepatitis C progression is commonly attributed to the continuous activation of the immune response with an increased production of pro-inflammatory cytokines, leading to fibrosis and ultimately to cirrhosis. On the contrary, anti-inflammatory cytokines, mainly interleukin (IL)-10 have a modulatory effect on hepatic fibrogenesis. The association between individual polymorphisms within cytokine genes and hepatitis C outcome is often weak and non-informative. Interestingly, it has been demonstrated that a combination of specific genotypes may be a more significant and powerful approach for predicting disease risk.
This study is aimed at investigating the combined effect of single nucleotide polymorphism (SNP) in IL-18 (-607C/A, -137G/C), interferon (IFN)-γ (+874T/A) and IL-10 (-1082G/A) genes on cirrhosis risk in HCV-infected patients.
Seventy-seven chronic hepatitis C Tunisian subjects were included in this study. The patients were divided into two groups: the first included 31 non-cirrhotic patients, and the second included 46 liver cirrhosis patients. IL-18 genotyping was performed using the PCR amplification and the restriction fragment length polymorphism analysis (RFLP). IFN-γ and IL-10 polymorphisms were analyzed using the allele-specific PCR (AS-PCR).
The combined high-risk genotype (IL-18 -607C/*, IL-18 -137G/*, IFN-γ +874T/*, IL-10 -1082A/A) frequency was compared between patients with and those without cirrhosis. Individuals were classified according the number of high-risk genotypes as follows: (0-2), patients with at most two high-risk genotypes; (3-4), patients with at least three of the high-risk genotypes. The logistic regression analysis showed that patients harboring 3-4 putative high-risk genotypes have a fivefold higher risk for developing cirrhosis in comparison to those harboring at most two high-risk genotypes (OR = 5.19; 95% CI = 1.49-18.05; p = 0.009).
Our study showed that the co-inheritance of IL-18, IFN-γ and IL-10 specific high-risk genotypes is associated with a greater risk for liver cirrhosis.
Hepatology International 06/2011; 5(2):681-7. · 2.64 Impact Factor
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Wijden Mahfoudh,
Noureddine Bouaouina,
Slim Ben Ahmed, Sallouha Gabbouj,
Jingxuan Shan,
Rebecca Mathew,
Nancy Uhrhammer,
Yves-Jean Bignon,
Wafa Troudi,
Amel Ben Ammar Elgaaied,
Elham Hassen,
Lotfi Chouchane
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ABSTRACT: Germ-line mutations in BRCA1 breast cancer susceptibility gene account for a large proportion of hereditary breast cancer families and show considerable ethnic and geographical variations. The contribution of BRCA1 mutations to hereditary breast cancer has not yet been thoroughly investigated in Middle Eastern and North African populations. In this study, 16 Tunisian high-risk breast cancer families were screened for germline mutations in the entire BRCA1 coding region and exon-intron boundaries using direct sequencing. Six families were found to carry BRCA1 mutations with a prevalence of 37.5%. Four different deleterious mutations were detected. Three truncating mutations were previously described: c.798_799delTT (916 delTT), c.3331_3334delCAAG (3450 delCAAG), c.5266dupC (5382 insC) and one splice site mutation which seems to be specific to the Tunisian population: c.212 + 2insG (IVS5 + 2insG). We also identified 15 variants of unknown clinical significance. The c.798_799delTT mutation occurred at an 18% frequency and was shared by three apparently unrelated families. Analyzing five microsatellite markers in and flanking the BRCA1 locus showed a common haplotype associated with this mutation. This suggests that the c.798_799delTT mutation is a Tunisian founder mutation. Our findings indicate that the Tunisian population has a spectrum of prevalent BRCA1 mutations, some of which appear as recurrent and founding mutations.
Molecular Biology Reports 05/2011; 39(2):1037-46. · 2.93 Impact Factor
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ABSTRACT: The prognostic value of the Epstein-Barr virus (EBV) DNA load in sera of nasopharyngeal carcinoma (NPC) patients measured before any treatment, after treatment and before relapse was assessed. The real-time polymerase chain reaction was used to detect the viral load levels among 74 NPC subjects. Patients were followed up for a period going from 1 to 6 years (median 4 years). Before treatment, the EBV DNA load was correlated with lymph node involvement and advanced stages. After treatment, the viral load level declined significantly and patients presenting a viral load level lower than 1000 copies/ml showed a better overall survival (OS). Moreover, a significant result was found when the 6-year OS rates of patients having fewer or more than 15,000 copies/ml of viral load before relapse were compared. These results suggest that the EBV DNA load quantification after treatment may be a useful predictor of disease progression and survival.
Biomarkers 05/2011; 16(3):274-80. · 2.21 Impact Factor
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ABSTRACT: Apolipoprotein A1 (ApoA1) is the major apoprotein constituent of high-density lipoprotein that can play important roles in tumor invasion and metastasis. In the current report, we evaluated the role of the functional ApoA1 polymorphisms (-75 G/A and +83 C/T) as genetic markers for breast cancer susceptibility and prognosis. We used the polymerase chain reaction and restriction enzyme digestion (RFLP-PCR) to characterize the variations of the ApoA1 gene in 295 unrelated Tunisian patients with breast carcinoma and 197 healthy control subjects. No association was found between the +83 C/T genetic variation in ApoA1 gene and the risk of breast cancer occurrence. The presence of the (+83) T allele appeared however to be associated with an increased risk of lymph node metastasis occurrence (OR = 2.94; P = 0.01). Furthermore, a positive association was found between ApoA1 -75 A allele carriers and breast cancer risk (OR = 1.57; P = 0.02). Regarding prognostic indicators, a significant association was found between ApoA1 (-75) A allele carriers and the premenopausal status of breast cancer patients (OR = 1.73; P = 0.03). Additionally, the presence of the -75 A allele was correlated with the oestrogen receptor status among premenopausal women (OR = 2.45; P = 0.02). This is the first report on the studies of ApoA1 single nucleotide polymorphisms (SNPs) in breast carcinomas. Our data suggest that these genetic variations of ApoA1 may represent a marker for the increased risk of breast cancer.
Molecular Biology Reports 03/2011; 38(3):1637-43. · 2.93 Impact Factor
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ABSTRACT: Nasopharyngeal carcinoma (NPC), a cancer with a remarkable geographical and worldwide ethnic distribution, has been strongly associated with human leukocyte antigen (HLA) class I genes. The presence of additional HLA risk factors has been suggested by several reports. In the present study, we analyzed the implication of HLA-E gene polymorphisms in NPC susceptibility in Tunisians, a population characterized by an intermediate incidence of NPC with specific clinical features. Peripheral blood DNA was obtained from 185 patients with NPC and 177 matched controls. Genotyping for three single-nucleotide polymorphisms, codon 83Gly/Arg, codon 157Arg/Gly, and codon 107Arg/Gly, was performed using the polymerase chain reaction method. The HLA-E*01:01 and HLA-E*01:03 were the only alleles found among Tunisians. The HLA-E*01:03 allele had a slight increase in patients with NPC (43%) compared with controls (37%), but the difference did not reach a statistical significance. Our results show the lack of association between HLA-E alleles and NPC in the Tunisian population. This is not in agreement with the previous studies, suggesting a potential implication of HLA-E gene polymorphisms in the susceptibility to NPC among populations with high-risk incidence. Our study further supports the dissimilarity of NPC between populations with different NPC incidence.
DNA and cell biology 02/2011; 30(8):603-9. · 2.28 Impact Factor
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ABSTRACT: The expression of human leukocyte antigen-G (HLA-G) in tumor cells may facilitate the escape of the tumor from immunosurveillance; thus the aim of this study was to evaluate the influence of HLA-G polymorphisms occurrence on nasopharyngeal carcinoma (NPC) susceptibility, severity, and survival. Using the restriction fragment length polymorphism-polymerase chain reaction and the amplification refractory mutation system-polymerase chain reaction method, 186 Tunisian patients and 189 healthy controls were genotyped for nonsynonymous polymorphisms in HLA-G codon 31Thr/Ser, codon 110Leu/Ile and codon 130Leu/framshift. When allele, genotype and haplotype frequencies between patients and controls were compared for each single nucleotide polymorphisms (SNP), no statistical significant differences were observed. According to the lymph node status and the tumor stages, the Ile110 allele was shown to be significantly less frequent among patients with a positive lymph node status and more severe tumor stages (stage I-II vs III-IV), respectively. Moreover, the codon 130C deletion occurrence was significantly associated with a decreased NPC free disease and overall survival. Altogether our results suggest a possible role for HLA-G locus in NPC progression and aggressiveness.
Human immunology 10/2010; 72(2):150-8. · 2.55 Impact Factor
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ABSTRACT: E-cadherin is a cell structural protein that has a pivotal role in cell-cell adhesion and epithelial development. Up to now, loss of activity of E-cadherin is believed to contribute to progression in several neoplastic diseases of epidermoid origin including nasopharyngeal carcinomas (NPC) by increasing invasion and proliferation. Besides, functional genetic variations in the promoter region of the E-cadherin gene have been associated with susceptibility to several neoplasms. In the current study we investigated the impact of the functional C/A genetic polymorphism at -160 from transcriptional start site of the E-cadherin gene promoter on susceptibility and prognosis in NPC.
A PCR and restriction fragment length polymorphism analysis was used to determine the variation of the -160C/A promoter region in a Tunisian population consisting of 162 NPC patients and 140 age matched healthy controls. Associations of the genetic markers with the clinicopathological parameters and the rates of the nasopharyngeal carcinoma-specific overall survival and the disease-free survival were also assessed.
A significantly increased risk of NPC was observed for carriers of E-cadherin -160A allele (OR=2.02; P=0.008). AA and CA genotypes entailed a 4.12 and 1.8 fold high risks, respectively for NPC compared to the CC genotype. Additionally, an association was ascertained between the E-cadherin polymorphism and the young age onset of NPC.
This is the first report on the studies of functional E-cadherin polymorphisms in NPC and our preliminary results suggest that the -160 C/A promoter polymorphism is associated with increased risk of nasopharyngeal carcinoma in the Tunisian population, especially in young patients.
Clinica chimica acta; international journal of clinical chemistry 05/2010; 411(17-18):1253-7. · 2.54 Impact Factor
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Nadia Bouzgarrou,
Elham Hassen,
Karim Farhat,
Olfa Bahri, Sallouha Gabbouj,
Nadia Maamouri,
Nabil Ben Mami,
Hammouda Saffar,
Abdelhalim Trabelsi,
Henda Triki,
Lotfi Chouchane
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ABSTRACT: Today there is increasing evidence concerning the contribution of pro-/anti-inflammatory cytokine balance and genetic factors in hepatitis C pathogenesis and interindividual heterogeneity of disease outcome. In the current study, we investigated the influence of functionally described single nucleotide polymorphisms (SNPs) present in interferon-gamma (IFNgamma) and interleukin-10 (IL-10) genes, on chronic hepatitis C severity. IFNgamma (+874T/A) and IL-10 (-1082G/A) genotypes were determined in 100 hepatitis C patients with different disease severities (chronic hepatitis, n = 42, liver cirrhosis [LC], and hepatocellular carcinoma in liver cirrhosis [HCC], n = 58) and 103 healthy controls using allele-specific polymerase chain reaction. No statistical differences in allele or genotype distributions of IFNgamma and IL-10 genes were observed between patients and controls. However, some significant differences in IFNgamma genotype frequencies were observed between the two groups of patients. IFNgamma(high producer) genotypes TT and TA were significantly more common in patients with LC and HCC (odds ratio = 2.65; p = 0.019). Although IL-10 genotypic frequencies were comparable between the different clinical forms of the disease, the combination of IFNgamma(low producer) and IL-10(high producer) genotypes was significantly associated with a lower risk of LC and HCC (odds ratio = 0.21; p = 0.015). In conclusion, our findings suggest that the imbalance between the pro-inflammatory and anti-inflammatory responses mediated by polymorphisms in the IFNgamma and IL-10 genes may influence the outcome of chronic HCV infection.
Human immunology 05/2009; 70(4):230-6. · 2.55 Impact Factor
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ABSTRACT: There is growing evidence suggesting that IL-18 levels may affect individual to virus-associated neoplasia and that single nucleotide polymorphisms (SNPs) within the gene may influence its production. In this study we wanted to know whether IL-18 polymorphisms at positions -607 C/A and -137 G/A are associated with susceptibility and/or are markers of nasopharyngeal carcinoma (NPC) prognosis.
Using the restriction fragment length polymerase chain reaction (RFLP-PCR), 163 Tunisian patients and 164 healthy controls were genotyped.
No significant association was found between each studied polymorphism and NPC. However, we noted that the -607 A allele, which is associated with lower IL-18 production, increased the risk of advanced tumor stages (OR=3.59; P=0.017) and that this risk was more pronounced among the older patient's age at onset (OR=3.85; P=0.012). Moreover, the significant difference in CA/GG haplotype frequency distribution between young and older patients supported the idea that NPC disease has biologically different features between age sub-groups.
Functional IL-18 gene polymorphisms do not influence the susceptibility to NPC in Tunisians but may contribute to disease onset and aggressiveness.
Cytokine 07/2008; 43(2):132-7. · 3.02 Impact Factor
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ABSTRACT: Xenobiotic Metabolizing Enzymes (XMEs) contribute to the detoxification of numerous cancer therapy-induced products. This study investigated the susceptibility and prognostic implications of the CYP2E1, CYP2C19, CYP2D6, mEH and NAT2 gene polymorphisms in breast carcinoma patients.
The authors used polymerase chain reaction and restriction enzyme digestion to characterize the variation of the CYP2E1, CYP2C19, CYP2D6, mEH and NAT2 gene in a total of 560 unrelated subjects (246 controls and 314 patients).
The mEH (C/C) mutant and the NAT2 slow acetylator genotypes were significantly associated with breast carcinoma risk (p = 0.02; p = 0.01, respectively). For NAT2 the association was more pronounced among postmenopausal patients (p = 0.006). A significant association was found between CYP2D6 (G/G) wild type and breast carcinoma risk only in postmenopausal patients (p = 0.04). Association studies of genetic markers with the rates of breast carcinoma specific overall survival (OVS) and the disease-free survival (DFS) revealed among all breast carcinoma patients no association to DFS but significant differences in OVS only with the mEH gene polymorphisms (p = 0.02). In addition, the mEH wild genotype showed a significant association with decreased OVS in patients with axillary lymph node-negative patients (p = 0.03) and with decreased DFS in patients with axillary lymph node-positive patients (p = 0.001). However, the NAT2 intermediate acetylator genotype was associated with decreased DFS in axillary lymph node-negative patients.
The present study may prove that polymorphisms of some XME genes may predict the onset of breast carcinoma as well as survival after treatment.
BMC Cancer 02/2008; 8:109. · 3.01 Impact Factor
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ABSTRACT: Matrix metalloproteinases (MMPs) are proteolytic enzymes that play important roles in tumor invasion and metastasis by degrading extracellular matrix components. Genetic variations in promoter regions of MMP genes, affecting their expression, have been associated with susceptibility to cancers. The aim of this study was to investigate the susceptibility and prognostic implications of the MMP-1 (-1607) 1G/2G and MMP-9 (-1562) C/T polymorphisms in nasopharyngeal carcinomas.
The variation of the MMP-1 and MMP-9 promoter regions in 174 patients with NPC and 171 healthy control subjects was investigated. Association of the clinico-pathologic parameters and the genetic markers with the rates of the nasopharyngeal carcinoma-specific overall survival and the disease-free survival were assessed using univariate and multivariate analyses.
No association was found between genetic variation in MMP-9 and the risk of NPC occurrence. In contrast, a significantly increased risk of NPC was associated with the homozygous MMP-1 (-1607) 2G2G genotype (OR=2.27; p=0.02). A significant association was also found between the 2G2G genotype and the aggressive forms of NPC as defined by large tumor size (T3-T4), lymph node metastasis and advanced stages (III-IV) at the time of diagnosis. Moreover, an association was ascertained between the MMP-1 polymorphism and gender (OR=2.90; p=0.02). In univariate analysis, the MMP-1 (-1607) 2G allele showed a significant association with reduced disease-free survival for NPC patients (p=0.03).
The genetic variation in MMP-1 may represent a marker for the increased risk of nasopharyngeal carcinoma.
Clinica Chimica Acta 10/2007; 384(1-2):57-63. · 2.54 Impact Factor
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ABSTRACT: To find out whether polymorphisms 333-Ile/Val and 637-Asp/Gly of the transporter part of the antigen processing 1 gene (TAP1) are associated with the development of nasopharyngeal carcinoma (NPC), we studied a total of 374 subjects (209 patients and 165 controls). We used the amplification refractory mutation system polymerase chain reaction (ARMS-PCR) method for analyzing the TAP1 gene polymorphisms. We found a significant difference between the patients and the controls in both the TAP1 codon 333 and codon 637 (P = 0.009 and P = 0.002, respectively). We also found that genotypes with the A allele were present in 206 patients with NPC and 155 controls (98.5 vs. 93.9%; P = 0.032; OR = 4.43) and that genotypes with the B allele were more often present in the control group (45 vs. 32%; P = 0.004; OR = 0.48), suggesting a significant positive association of the A allele with NPC risk and a protective role of the B allele. We have observed an association between the distribution of TAP1 alleles and the NPC patient's age at onset, compared with controls. These results back up the fact that the etiology of NPC in intermediate-risk countries is completely different in each peak of age prevalence and that each peak may possess its own particular oncogenic mechanism.
Cancer Genetics and Cytogenetics 06/2007; 175(1):41-6. · 1.39 Impact Factor
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ABSTRACT: Angiogenesis plays an important role in the initiation and progression of many malignancies including prostate cancer (PCa). Therefore, genes implicated in angiogenic pathways could be susceptibility candidate genes for this malignancy. In this respect, we investigated the impact of functional genetic variants of TSP1 (N700S) and MMP9 (-1562 C/T) genes on the development and progression of PCa. This case-control study included 101 PCa patients and 106 healthy controls analyzed by polymerase chain reaction -restriction fragment length polymorphism assay. No association was observed between any of the TSP1 genotypes and PCa risk or severity; however, subjects carrying one copy of the MMP9 T allele exhibited threefold higher risk of developing PCa (OR = 2.86; P = 0.004). Regarding prognostic value, a significant association was found between the occurrence of the MMP9 T allele and the high-grade tumor (OR = 3.21; P = 0.004) and the advanced disease (OR = 2.47; P = 0.026). We also analyzed the effect of the combined genotypes on PCa risk. The patients with two high-risk genotypes exhibited 2.8-fold higher risk of developing PCa than those with only low-risk genotypes, but the association was not statistically significant. These findings suggest that MMP9 polymorphism is an independent risk factor of PCa development and aggressiveness.
Cancer Genetics and Cytogenetics 02/2007; 172(1):38-44. · 1.39 Impact Factor
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ABSTRACT: Loss of FAS (CD95) expression is a common feature of malignant transformation, which has been related to loss of epithelial cell differentiation and loss of sensitivity to apoptosis. We investigated the potential association between FAS promoter polymorphism and the genetic susceptibility to the Epstein-Barr virus (EBV)-related nasopharyngeal carcinoma. The in vivo functional significance of the FAS polymorphism was investigated by assessing the correlation between FAS genotypes and the presence of autoantibodies to cytoskeleton and nuclear antigens frequently detected in nasopharyngeal carcinoma. We determined the FAS polymorphism distributions by RFLP-PCR in 170 patients with nasopharyngeal carcinoma and in 224 sex and age-matched controls. We used ELISA and the immunofluorescence analysis to characterize the presence of IgG autoantibodies to the cytoskeleton and nuclear proteins in patients' sera. A significantly increased risk of nasopharyngeal carcinoma was associated with heterozygote FAS-A/G (OR=2.00, P=0.001) and homozygote FAS-G/G (OR=3.19, P=0.0001) variants. The increased frequency of FAS-G/G genotype is correlated with the presence of anti-nuclear autoantibodies in patients with nasopharyngeal carcinoma (P=0.0298). Our results demonstrated that FAS promoter polymorphism was significantly associated with the nasopharyngeal carcinoma in Tunisians. The anti-nuclear autoantibodies induction was also found to be related to FAS polymorphism. The FAS promoter polymorphism associated not only with the increased risk of nasopharyngeal carcinoma in Tunisians but also with immune response deregulation observed in this cancer.
Cancer Letters 03/2006; 233(1):21-7. · 4.24 Impact Factor
